You could choose to target the creature you're going to sacrifice to pay for Bone Splinters. First you choose the target (at which time it's still on the battlefield), then you pay the costs (at which time you sacrifice it). The spell will be countered.

4/15/2013

You must sacrifice exactly one creature to cast this spell; you cannot cast it without sacrificing a creature, and you cannot sacrifice additional creatures.

4/15/2013

Players can only respond once this spell has been cast and all its costs have been paid. No one can try to destroy the creature you sacrificed to prevent you from casting this spell.